Load Range C is a weight rating that tells you the maximum load a single trailer tire can safely carry at a given pressure

Load Range C is a classification system for trailer tires that indicates how much weight one tire can support. The letter — in this case C — corresponds to a specific maximum load capacity and the air pressure needed to achieve it. A Load Range C tire can carry more weight than Load Range B, but less than Load Range D or E. The rating appears on the tire's sidewall and is essential information for matching tires to your trailer's actual weight.

The load range does not tell you the weight limit of your entire trailer. Instead, it tells you what one tire can handle. To find your trailer's weight limit, you divide the trailer's gross vehicle weight rating (GVWR) by the number of tires. Then you compare that per-tire load to what your tires are rated for. If your calculation shows each tire must carry more weight than its load range permits, the tires are undersized for your trailer.

Key Takeaways

  • Load Range C tires are rated for specific maximum loads at specific air pressures, both printed on the tire sidewall.
  • You must divide your trailer's GVWR by the number of tires to find the load each tire must carry, then compare that to the tire's rating.
  • Load Range C tires require higher air pressure than Load Range B but lower pressure than Load Range D, and pressure affects how much weight the tire can hold.
  • Underinflating a Load Range C tire below its rated pressure reduces its load capacity and increases heat buildup, which can cause blowouts.
  • Trailer tires wear differently than car tires because trailers do not have engines to power them, so Load Range C tires may last longer if properly maintained.

How Load Range C Compares to Other Trailer Tire Ratings

Trailer tires come in Load Range B, C, D, and E. Each step up represents a heavier-duty tire designed to carry more weight. Load Range B is the lightest and is used on small utility trailers and boat trailers. Load Range C is the middle ground and appears on many enclosed cargo trailers, utility trailers, and small horse trailers. Load Range D and E are for heavier commercial trailers and tandem-axle setups.

The difference between load ranges is not just the maximum weight — it is also the air pressure. A Load Range C tire might be rated for 1,760 pounds at 65 psi, while a Load Range D version of the same tire size might be rated for 2,150 pounds at 80 psi. Higher pressure means the tire's sidewall is reinforced to handle more stress. Using a Load Range B tire on a trailer that needs Load Range C creates a safety risk because the tire will overheat and fail under the actual load, even if it looks fine from the outside.

Reading the Load Range C Rating on Your Tire Sidewall

The load range letter and the maximum load capacity are printed on the tire's sidewall. You will see something like "Load Range C" followed by a number in pounds, such as "1,760 lbs" or "Max Load 1,760 lbs." Next to that is the required air pressure, often written as "65 psi" or "Max Pressure 65 psi." Both numbers are critical — the load rating is only valid when the tire is inflated to that exact pressure.

Some tires also show a ply rating, which is an older system that roughly correlates to load range. A 6-ply tire is often similar to Load Range C, though ply rating and load range are not identical. Always use the load range letter and the specific load and pressure numbers, not the ply rating, to determine whether a tire is right for your trailer. If you cannot find this information on your tire, check the tire manufacturer's website or contact them directly with your tire size and model number.

Calculating Whether Load Range C Is Enough for Your Trailer

Start with your trailer's GVWR, which is printed on the trailer's VIN plate or in the owner's manual. This is the maximum total weight the trailer is designed to carry, including the trailer itself. Subtract the trailer's dry weight (weight with no cargo) to find the cargo capacity. Then divide the GVWR by the number of tires on the trailer. This gives you the maximum load each tire must support.

For example, a trailer with a GVWR of 7,000 pounds and four tires must distribute that weight across four tires, meaning each tire carries up to 1,750 pounds. If your Load Range C tires are rated for 1,760 pounds at 65 psi, they will work — but only if you keep them at exactly 65 psi. If you run them at 60 psi, their load capacity drops, and you are overloading them. If your calculation shows each tire must carry 1,900 pounds, Load Range C is not sufficient, and you need Load Range D.

Air Pressure and Load Range C Performance

Load Range C tires must be inflated to their rated pressure to deliver their rated load capacity. The pressure is not a suggestion or a range — it is the pressure at which the tire's internal structure is designed to work. Underinflating a Load Range C tire by even 5 psi reduces its load capacity and causes the sidewalls to flex more than intended, generating excess heat. This heat buildup is the primary cause of trailer tire blowouts.

Overinflating a Load Range C tire above its rated pressure does not increase load capacity; it only makes the tire ride harder and wear unevenly. Check your tire pressure with a quality gauge at least once a month and before every long trip. Tire pressure changes with temperature — cold weather lowers pressure, and hot weather raises it — so check pressure when the tires are cool, before you have driven the trailer. Many trailer owners keep a portable air compressor and gauge in their vehicle specifically for this reason.

Common Mistakes With Load Range C Tires

The most common mistake is assuming that because a tire looks fine, it is safe to use. A Load Range C tire that is underinflated or overloaded will not show obvious damage until it fails suddenly. Another mistake is mixing load ranges on the same trailer — using Load Range B on one axle and Load Range C on the other. This creates uneven weight distribution and causes the lighter-rated tires to fail first.

A third mistake is ignoring the age of the tire. Trailer tires can sit unused for long periods, and the rubber degrades even when the trailer is parked. A Load Range C tire that is more than five to seven years old should be inspected by a tire professional, even if the tread looks acceptable. Dry rot and sidewall cracking are common in older trailer tires and can cause sudden failure. If you store your trailer for the winter or long periods, cover the tires to protect them from UV exposure.

When to Replace Load Range C Tires

Replace Load Range C tires when the tread depth reaches 2/32 of an inch, which is the legal minimum. You can check this with the penny test — insert a penny into the tread with Lincoln's head upside down; if you can see the top of his head, the tread is too worn. Trailer tires wear differently than car tires because the trailer is not powered by an engine. The tires do not grip the road to accelerate or brake; they straightforward roll. This means trailer tires often last longer than car tires if they are properly inflated and the trailer is not overloaded.

Replace tires when ready if you see sidewall cracks, bulges, or punctures that cannot be repaired. A Load Range C tire with sidewall damage is not safe to use, even if the tread is good. If you have a blowout, do not attempt to repair the tire yourself — have it inspected by a tire professional. Many blowouts are caused by overloading or underinflation, so if one tire fails, the others may be at risk as well.

Frequently Asked Questions

Can I use Load Range B tires on a trailer that came with Load Range C?

No. Load Range B tires have a lower maximum load capacity and require lower air pressure. Using them on a trailer designed for Load Range C will cause them to overheat and fail, especially on long trips or in hot weather. Always match the load range to your trailer's GVWR and per-tire load requirement.

What happens if I overinflate a Load Range C tire above its rated pressure?

Overinflating does not increase the load capacity — it only makes the tire ride harder, wear unevenly in the center, and become more prone to damage from road hazards. Stick to the pressure printed on the tire sidewall. If you need more load capacity, upgrade to Load Range D, not higher pressure.

Do Load Range C tires last longer than Load Range B?

Not necessarily. Tire life depends on inflation pressure, load, driving conditions, and storage. A properly maintained Load Range C tire may last longer than an underinflated Load Range B tire, but an overloaded Load Range C tire will fail quickly. Maintenance matters more than the load range itself.

How do I know if my trailer needs Load Range C or Load Range D?

Divide your trailer's GVWR by the number of tires. If the result is less than the Load Range C maximum load at the rated pressure, Load Range C is sufficient. If it exceeds the Load Range C rating, you need Load Range D. Check the tire sidewall for the exact load and pressure numbers before deciding.